Answer: bottom left
4x+2y+15
Step-by-step explanation:
3x + x=4x
5 + 10= 15
2y=2y
4x+2y+15
Ex.
f + g = y
-----------
3
3(f+g) = (y) 3
--------
3
f + g =3y
f - f + g = 3y - f
g = y - f
So what they are saying is the sum of 2x +13=75
Therefore we can just solve for 2x, our unknown value.
2x+13=75 now subtract 13 and divide by 2 from both sides of equation to not change the equation
x+13-13=75-13
This leaves us with
x=(75-13)/2=31 therefore x=31 or our unknown value is 31.
I hope this helped. Any questions please just ask. Thank you.
Answer:
Mean = 528 ppm
Standard deviation = 90.8 ppm
Step-by-step explanation:
Assuming a basis of 100 trees
6 trees with 350 ppm (minimal growth)
10 trees with 450 ppm (slow growth)
47 trees with 550 ppm (moderate growth)
37 trees with 650 ppm (rapid growth)
Mean = xbar = Σx/N
x = each variable
xbar = mean
N = number of variables = 100
Σx = sum of all variables = sum of all the ppm = (6×350) + (10×450) + (47×550) + (37×550) = 52800
xbar = 52800/100 = 528 ppm
Standard deviation = σ = √[Σ(x - xbar)²/N]
x = each variable
xbar = mean = 528
N = number of variables = 12
Σ(x - xbar)² = [6(350 - 528)²] + [10(450 - 528)²] + [47(550 - 528)²] + [37(650 - 528)²] = 824400
σ = √[Σ(x - xbar)²/N] = √(824400/100) = 90.8 ppm
Those shapes are all rectangle